Knife sharpening device



Nov. 18, 1947. H. c, MILLER f 2,431,188

KNIFE SHARPENING DEVICE Filed Feb. '20, 1946 INVEN TOR. HOWARD C. M/LLER.

BY m; ATTORNEYS.

Patented Nov. 18, 1947 UNITED STATES PATENT OFFICE KNIFE SHARPENING DEVICE Howard C. Miller, New York, N. Y.

Application February 20, 1946, Serial No. 648,844

3 Claims.

This invention relates to new and useful improvements in knife sharpening devices.

An object of the invention is to provide a simple, efficient, economical, and durable device for sharpening knives which can be simply operated and either held in the hand and rest upon a support during operation, or fastened to a rigid support.

A further object is to provide a device having a pair of abrasive rollers which sharpen the knife and related to facilitate turning of the same about their axes to present fresh sharpening surfaces to the knife'to be sharpened.

Still further the object of the invention is to provide means whereby the rollers are held in proximity but relatively free to turn when not in use, and associated with means to hold them closely together when in use.

Further and more specific objects, features, and advantages will more clearly appear from a consideration of the Specification hereinafter set forth especially when taken in connection with the accompanying drawing which illustrates two forms which the invention may assume and which form part of the specification.

In the most general and brief terms, the invention has to do with a pair of closely disposed sharpening rollers supported on a frame in adjacent relation, with means on the frame to prevent upward and endwise movement of the rollers, and means also associated with the rollers and the frame to press them together when they are to be employed to sharpen a knife.

Another feature concerns the nesting of the rollers with their ends freely lying in cutaway recesses in the walls of the frame and means on the frame to restrict endwise movement, the walls of the recesses shaped to restrict movement of one of said rollers and means also provided to press or be pressed against the other roller to restrict its movement and hold it in proper contact with the first roller when sharpening is taking place.

The present preferred forms which the invention may assume are illustrated in the drawings of which,

Figure 1 is a perspective view of a form of the device which is adapted to be held in the hand.

, Figure 2 is a vertical longitudinal sectional view therethrough, the sharpening rollers being shown in free separated position in full lines and in contacting engagement for use in dot and dash lines.

Figure 3 is a vertical cross sectional view taken On the line 3-3 of Figure 2.

Figure 4 is a perspective view of another form of the device which is adapted to be fastened to a fixed support.

Figure 5 is a vertical longitudinal sectional view taken on the line 5-5 of Figure 4.

In considering the construction illustrated in Figures 1, 2, and 3, it is to be noted that there is provided a frame A, preferably open at its top and bottom and provided with spaced rectangularly disposed walls III, II, I2, and I3. The frame may be constructed of metal, plastic or other suitable material. On this frame A are adapted to be disposed in close adjacent relation 2. pair of sharpening rollers I4 and I5 of any suitable material for sharpening knives by drawing the knife in the usual manner longitudinally between the rollers as shown in dotted lines in Figure 2. The

rollers I 4 and I5 are preferably made of carborundum or other like abrasive material. In order to support the rollers I 4 and I5 on the walls II and I3 as shown, said walls are cut away to form opposed recesses I6 in which the ends of the rollers I4 and I5 lie with the remainder of the rollers extending between the .walls. In the form under description a limiting plate I1 is integral with the walls II and I3 or fastened thereto in any desired manner and which extend across thegaps formed by the recesses IE to prevent longitudinal movement of the rollers. Each limiting plate II has a V-shaped notch I8 formed therein in line with the line of contact of the adjacent rollers to permit the drawing of the lmife horizontally along the junction surfaces between the rollers I4 and I5.

The top of the end walls of the recesses I6 adjacent the roller I5 are sloped inwardly slightly over said roller as at I 9 to prevent upward movement thereof. Adjacent the other roller I4 is a presser block 20 having a front surface 2I sloping inwardly over the roller I4 similar to the slope of the walls I9 of the frame which are disposed over the roller I5. This block or member 20 is pivoted to the side walls II and I3 at 22 and has an integral fiat portion 23 extending rearwardly therefrom across the top of the wall I 0 and then upwardly and outwardly in the form of a handle 24 by means of which the device can be grasped by the hand of the operator. The block 20 and the portion 23 and the front surface 2| thereof are so related that when the portion 23 is lying flat on the top of wall III the sloping surface 2| is slightly removed from the roller I4 but nevertheless will prevent its upward movement to any appreciable extent. However, when the device is to be used, the thumb of the operator in whose hand the handle 24 is grasped will press on the top of the block 20 and cause the same to swing down to bear against the roller I l and move it into tight engagement with the other roller I5, especially when in use and the knife blade B is being drawn across between the tWo rollers. When the thumb is released from the block 20, the rollers are released and are free to move around their axes. Thus the rollers during sharpening are held rather tightly together but otherwise are free to move around their axes and in this manner they will constantly change their position to present fresh sharpening surfaces for subsequent use.

It will therefore be seen that in this form the rollers are disposed adjacent each other on and across the opposed Walls of the frame and some what free to roll except during sharpening operations. Means are provided to limit their endwise movement and means are also provided to hold them together during the sharpening operation, in this particular case one of the latter means is manually manipulable.

In the modified form shown in Figures 4 and 5 I still employ the open frame A having walls ill, I 1, l2, and is with the cutaway recesses 16 having on one side the sloping wall I!) to limit the movement of the roller [5. The endwise movement of the rollers is prevented by means of integral upturned outwardly offset spaced fingers 25 the upper ends of which bear against the respective ends of the rollers. In order to hold the other roller i l in proximity and in rubbing contact with the roller at the desired pressure there is provided a movable plate 26- to which is connected one end of a contracting spring 2?, the other end of which is. connected to the wall l2 and thus tends to pull the plate 26 to the right. The plate has upturned hook-like fingers 28 spaced apart thereon and preferably struck up therefrom to lie against and partly around the adjacent surface of the roller M to serve as the means to press against the roller ill and hold it in proper position against theother roller 15. Extending rearwardly from the plate 26 is an upwardly sloping arm 29 having a downwardly bent end 3E! adapted to rest upon the outer edge of the top of the wall H3 as shown.

In operation of this form of the invention, the spring 21 normally keeps the rollers pressed together at a desired pressure so that a knife may be drawn betweenthe sharpening rollers I l and [5 without causing the rollers to become separated. To change the position of the contacting surfaces of the sharpening rollers, the operator pushes outwardly upon the arm 29 against the action of the spring 21 causing it to move away from the wall in and consequently causing the hook-like fingers 28 to move awayfrom the. roller 14, thus releasing the same. Both rollers I l and I5 are now free and may be manually turned by the fingers of an operator to change the position of the confronting sharpening surfaces.

It will therefore be seen that in this form of the invention the rollers are disposed. adjacent the frame in stationary position and provided with means to limit their upwardand endwise claim as new and desire to secure by Letters each other on and, across the opposed walls of 4 movement. The frame shown in Figure 4 is provided with opposed perforated ears 3! whereby it may be fastened to a fixed support.

While the invention has been described in detail and with respect to present preferred forms which the invention may assume, it is not to be limited to such details and forms since many changes and modifications may be made in the invention without departing from the spirit and scope of the invention in its broadest aspects. Hence it is desired to cover any and all forms and modifications of the invention which may come within the language or scope of any one or more of the appended claims.

Having thus described my invention, what I Patent is:

1. In a device of the class described, a frame having spaced parallel walls, sharpening rollers adjacently disposed thereon, said walls having cut-away recesses in which the ends of said rollers lie, the walls of the recesses adjacent one roller overlapping same to restrict the upward movement of said roller, and means movably secured to the casing to engage the other roller to press it against the first roller.

2. In a device of the class described, a frame having spaced walls, sharpening rollers disposed thereon in close proximity, said walls having cutaway recesses in which the ends of said rollers lie, said walls on the side of one roller overlapping the latter to restrict its upward movement, a block pivoted to the frame adjacent the other roller and having a surface to press against said other roller when the thumb of the hand of an operator presses on said block, and a handle connected to the block.

3. In a device of the class described, a frame having walls with cut away recesses in the opposite sides, sharpening rollers disposed side by side and having their ends in said recesses, the walls being shaped at said recesses to overlap one of said rollers, plates on the outer faces of said rollers, extending across the recesses to limit the endwise movement of the rollers, said plates having notches in line with the adjacent portions of said rollers to expose the ends thereof, a member pivoted to the frame adjacent the other roller in position to'move said otherv roller towards the aforesaid one roller, and a handle connected to said member.

HOWARD C. MILLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

